164 Cameron, The Ferruginous Rough-leg. [i^rU 



a large straggling edifice, three feet high and the same in diameter at 

 the most compact part. Near this eyrie were the four unoccupied 

 nests above mentioned. When Mr. Felton first discovered this 

 nest, on May 18, the female hawk was incubating four eggs, and the 

 young birds of about a week old were found on June 6. At about 

 a month old the nestlings were taken for pets by some Swede rail- 

 road contractors, greatly to the annoyance of the engineer, who 

 desired that as many as possible of his proteges should be safely 

 fledged. The young hawks were allowed full liberty in the con- 

 tractor's camp and would fly away in the morning and return 

 at night, but on July 28 they disappeared altogether. According 

 to Mr. Felton's observations and my own the Ferruginous Hawk 

 develops its flying powers very quickly, and I have known a two 

 months old female of this species to take flights of from two hundred 

 to three hundred yards without a wind. As with the genera Aquila 

 and Btdeo, the male is a week later than the female in acquiring 

 the full power of flight. 



The fourth eyrie, which contained four eggs, was placed upon 

 the summit of a sand rock among pines, and here four birds were 

 reared, which, as observed by Mr. Felton, took flight on July 17. 

 This nest was not measured until the day of the final departure of 

 its occupants, when.it had settled so much as to be only a foot and a 

 half high, although three and a half feet in diameter. 



Food. 



So far as I have been able to observe in Eastern Montana, the 

 Ferruginous Rough-leg feeds chiefly upon prairie dogs and meadow- 

 mice, though not averse to snakes. In my opinion it never takes 

 frogs. Like Golden Eagles, these hawks often hunt amicably in 

 pairs, and then appear to be more courageous, attacking mammals 

 as large as jack-rabbits. On July 29, 1907, Mr. Lance Irvine, 

 foreman of the Crown W. Ranch in Custer County, Montana, 

 when out riding, surprised a pair of Ferruginous Rough-legs with a 

 freshly killed jack-rabbit, which weighed about eight pounds, and 

 could not therefore be carried away. From the description this 

 pair would consist of a bird of the year with one of its parents. On 



